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What is the python “with” statement designed for?
...rom contextlib import contextmanager
import os
@contextmanager
def working_directory(path):
current_dir = os.getcwd()
os.chdir(path)
try:
yield
finally:
os.chdir(current_dir)
with working_directory("data/stuff"):
# do something within data/stuff
# here I am back...
What is a correct mime type for docx, pptx etc?
...
application/vnd.ms-excel is specifically for .xls files. the ability for it to work with .xlsx depends on the client software in use.
– Armand
Nov 4 '14 at 0:03
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How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...TE.
Quick explanation.
For usage see the manual - specifically the conflict_action clause in the syntax diagram, and the explanatory text.
Unlike the solutions for 9.4 and older that are given below, this feature works with multiple conflicting rows and it doesn't require exclusive locking or a retr...
Why are these numbers not equal?
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General (language agnostic) reason
Since not all numbers can be represented exactly in IEEE floating point arithmetic (the standard that almost all computers use to represent decimal numbers and do math with them), you will not always get what you expected. This is espe...
Drop rows with all zeros in pandas data frame
I can use pandas dropna() functionality to remove rows with some or all columns set as NA 's. Is there an equivalent function for dropping rows with all columns having value 0?
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WAMP 403 Forbidden message on Windows 7
I have installed WAMP version 2.1 on my windows 7 machine. When i browse to localhost in my browser, the WAMP server page is visible.
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Python and pip, list all versions of a package that's available?
Given the name of a Python package that can be installed with pip , is there any way to find out a list of all the possible versions of it that pip could install? Right now it's trial and error.
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What is the tilde (~) in the enum definition?
I'm always surprised that even after using C# for all this time now, I still manage to find things I didn't know about...
1...
How do I apply CSS3 transition to all properties except background-position?
I'd like to apply a CSS transition to all properties apart from background-position.
I tried to do it this way:
6 Answers
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generate days from date range
...) + (100 * c.a) + (1000 * d.a) ) DAY as Date
from (select 0 as a union all select 1 union all select 2 union all select 3 union all select 4 union all select 5 union all select 6 union all select 7 union all select 8 union all select 9) as a
cross join (select 0 as a union all select 1 union...